Box with automatic closure



ylfi, 1195? R. E. VAN ROSEN ,7

BOX WITH AUTOMATIC CLOSURE f 4 Sheets-Sheet 1 Filed Nov. 18. 1.953

5e l l r 78 1 l Ffi v I 68 as r ..L

' RE. VAN ROSEN 2,799,442

BOX WITH AUTOMATIC CLOSURE July 16,, 1957 4 Sheets-Sheet 2 Filed NOV.18, 1953 July 16, 1957 Filed Nov. 18, 1953 R. E. VAN ROSEN 2,799,442

BOX WITH AUTOMATIC CLOSURE I 4 Sheets-Sheet 3 JulylG, 1957 VAN ROSEN2,799,442

I BOX WITH AUTOMATIC CLOSURE 4 Sheets-Sheet 4 Filed Nov. 18, 1953 UnitedStates BOX WITH AUTOMATIC CLOSURE Application November 18, 1953, SerialNo. 392,937

3 Claims. (Cl. 229-37) The present invention relates to boxes and moreparticularly to an automatic self-closing closure for boxes of thegeneral type identified as folding boxes. According to the presentinvention a generally rectangular box having four vertical walls isprovided with one or more closure flaps each hinged along an upper orlower edge of one vertical wall and hingedly connected -by webs to thecorresponding edges of the walls on both sides of that "to which theclosure flap is hinged. The webs are provided with generally diagonallydisposed lines of weakening along which the webs may be folded inwardlyas the closure flap is moved toward closed position. According to thepresent invention, the lines of weakening in the webs are not trulydiagonal whereby the webs are somewhat distorted when the closure flapis moved toward closing position. The particular disposition of thelines of weakening is such that distortion of the webs yieldinglyresists movement toward closed position and maximum distortion occursbefore the closure flap reaches its final closed position. Continuedmovement of the closure flap toward closed position and beyond the pointof maximum distortion brings about a reversal or overcentering of thespring eflYect arising from such distortion and thereafter the distortedwebs serve to hold the closure flap in closed position. The closureflap, therefore, will snap into closed position or into opened positionWhenever it is moved in an appropriate direction beyond the point wheremaximum distortion of the webs occur.

A folding box with such automatic closure is particularly useful in theretail trade where a merchant may purchase the boxes in fiat, foldedcondition and set them up when they are needed for packaging ofmerchandise. After the merchandise has been inserted in the box, theclosure flap is moved toward closed position whereupon it snaps shut andthe purchaser may take the merchandise home without the necessity fortaping, tying with string, or the like. Furthermore, the box may 'beused by the purchaser for subsequent storage of the purchased articleinasmuch as the automatic closure may be operated repeatedly withoutdamage to the closure or to the box. The box of the present invention isparticularly useful, for example, in the merchandising of light, bulkyarticles such as hats, shoes, garments, and the like.

The closure of the present invention may be applied in the form of oneor more automatically closing flaps at atent O F the top or bottom orboth. If the closure of the presshapes and proportions and that thepresent invention 2,799,442 Patented July 16, 1957 ice shall not belimited to the specific disclosures herein made.

In the drawings:

Fig. 1 is a plan vietw of a blank from which one embodiment of thepresent invention may be constructed;

Fig. 2 is an elevational view of a box which has been set up from theblank of Fig. 1 and in which the closure flap has been slightly movedtoward closed position;

Fig. 3 is a view similar to Fig. 2 but showing the closure fiap movedfurther toward closed position;

Fig. 4 is a view similar to Fig. 2 but showing the box closed and withcertain parts broken away to disclose the position of the Webs whichserve to hold the closure flap in position;

Fig. 5 is a plan view of a blank from which a modified form of thepresent invention may be constructed;

Fig. 6 is a fragmentary elevational view of one end of a box made from ablank such as that shown in Fig. 5 and showing the closure slightlymoved toward closed position;

Fig. 7 is a fragmentary sectional view taken in a plane such as thatindicated at AA in Fig. 5, and showing the closure moved further towardclosed position; and

Fig. 8 is a view similar to Fig. 7 showing the closure in closedposition.

Referring now to the drawings, in Fig. 1 there is shown a blank for asimple rectangular box which may be of the general size and proportionsof the familiar shoe box. The blank includes a front wall 10, a rearwall 12, an end wall 14 interposed between the walls 10 and 12 andseparated therefrom by score lines 16 and 18. An opposite end wall 20 isseparated from the rear wall 12 by a score line 22. A glue tab 24 isjoined along a vertical edge of the end wall 20 by a score line 26. Glueor other suitable adhesive is positioned in the area indicated at 28 forsecuring the tab 24 to the left hand edge portion of the front wall 10as viewed in Fig. 1 in a manner well known in the art. A stiffeningflange 11 is joined along a score line 13 along the upper edge of thefront wall 10.

The blank may be provided with any suitable form of bottom closure flapsincluding flaps identical with the top closure flaps to be describedhereinbelow. For simplicity of disclosure, however, there is shownherein a simple bottom closure construction comprising end flaps 30 and32 joined with the end Walls 14 and 20 by score lines 34 and 36. A mainbottom closure flap 38 is joined along the lower edge of the front wall10 by a score line 40 and is provided with a tuck-in lip 42 hingedthereto along a score line 44. The simple bottom closure just describedis closed after the box has been erected by first folding the end flaps30 and 32 inwardly and thereafter folding the main bottom flap 38 alongthe score line 40. The tuck-in fiap 42 is inserted between the end flaps30 and 32 and the adjacent lowermost edge 46 of the rear wall 12. Theclosure just described forms no part of the present invention, it beingunderstood that any suitable form of bottom closure may be used so longas it is of the type which will tend to hold the box in erected positionfor insertion of contents through the top.

The top closure, in accordance with the present invention, comprises amain top panel 48 joined along a score line 50 with the rear wall 12.The main panel 48 is also joined along vertical score lines 52 and 54with webs 56 and 58 which have a generally triangular configuration andwhich are respectively joined with the end walls 14 and 20 alonghorizontal score lines 60 and 62. A line of weakening 64 extends fromthe intersection of the score lines 60 and 52 generally diagonally ofthe web 56 and in a particular angular relationship which will bedescribed hereinbelow. Such line of weakening may com r O prise a scoreline or a combination of scoring and cut ting as illustrated in thisparticular form of the invention. As shown in the drawings andparticularly in Fig. 1, the line of weakening 64 may comprise a cut 66which extends from the intersection of the score lines 60 and 52 for arelatively short distance beyond which there is a score line interruptedby an arcuately curved cut. 68 to define a tab 70 to be describedhereinbelow. Beyond the tab 70, the score line extends to the margin of'the web 56.. It will be apparent that the .web 56 will tend to foldalong the line of weakening 64 and that the tab 70 will projectoutwardly. when suchfold is made- The web 58 at the opposite .end of thebox is provided with a line of weakening indicated generally at 72 whichis-similar in all respects .with the line of weakening 64 and includes,for this particular form of the-invention a cut 71 and a curved portion75 defining a curved tab .73.

Since the box.which is to be erected from the blank shown in Fig. l is arectangular box, the walls 12 and '14 for example,. will occupy planeswhich intersect at right angles along the score line 18. Similarly, thescore lines 52 and 60 intersect at right angles. Therefore, thenaturalfold line for the web 56 would be along a line .bisecting .theanglebetween score lines .60 and 52. If:the line of weakening 64 were tobe thus disposed, the-web 56 could be foldedinwardly as the main closurepanel 48 is folded inwardly along its score line 50 Without distortionof the web 56 and such action would be resisted only by such spring asis left in the box board along-the score lines. This residual spring, ofcourse, would tend to-move the main closure panel upwardly and away fromclosed position. by precreasing, as to kill residual spring, the mainclosure panel 48 might lie limply in closed position but such a closureobviously would be of little value in maintaining contents within thebox. According to the present invention, the lines of weakening 64 and72 in the webs 56 and 58 do not bisect the angle between the respectivescore lines which define such webs. Thus the angle a between the scoreline 60 and the line of weakening 64 is slightly greater than the angle[2 between the line of weakening64 and the score line 52. Similarly, theangle is slightly greater than the angle d in the web 58. As a practicalmatter, the difference between the angles may be from one to fourdegrees. For example, angles a and c may be 46 and the angles 17 and dmay be 44, in a rectangular box of the type chosen for illustration.Since the lines of weakening 64 and 72 are thus displaced from thenatural fold lines of the webs 56 and 58, distortion will occur when thewebs are tucked inwardly incident to moving the main closure panel 43towards closed position.

The blank so far described may be erected into a fold ing box with aself-closing top closure which will automatically remain in closedposition as will be described hereinbelow. However, it has been foundpreferable to provide a reinforcing panel 74 joined to the top panel"64. At the lower end the panel 78 is cut at 38 at anangle to coincidegenerally with the edge 94 of the-web 56. The panel 80 is similarly cutat 90 and 92. be understood, however, that the particular conformationof the edges 94 and 96 of the webs 56 and 58 is not If the score lineswere so weakened, as

It will critical to the present invention and they might be curvedforwardly and downwardly-alongtheline 76--as-viewed- 4 in Fig. l, inorder that the reinforcing panel 74 may lie flatwise in registry withthe main panel 48 and the small panels 78 and 80 may lie in generalregistry with the triangular portions of the webs 56 and 58 which lieabove the lines of weakening 64 and 72.

The blank shown in Fig. 1 will normally be folded first along the lineestablished by the score lines 18, 52 and 82 to bring the glue tab 24 inposition to be secured to the front Wall 10. After it is thus securedthe blank is ready for shipment to the customer. When the customerdesired to set up the blank the various score lines describedhereinabove will be precreased in appropriate directions as is usual insetting up folding boxes. Thus the score lines 16 and 22 will be creasedso that the vertical walls 10, 14, 12 and 20 will define a hollowrectangle. The end flaps 30 and 32 of the bottom closure will be foldedinwardly and the main bottom panel 38 with its tuck-in tab 42 will bepositioned in known manner. The box then will be in openerectedposition. The stiifening flange 11 will be folded along the score line13 to extend inwardly of the box to stiffen the upper edge of the frontwall 10. The reinforcing panel 74 and small panels 78 and 80 will befolded downwardly along the line 76 to form the double thickness. topclosure flap. The box is now ready to be closed and this is effected bystarting the webs 56 and 58 to fold along their lines of weakening 64and 72, inwardly and downwardly of the mouth of the container. Thisbrings the container into the position illustrates in Fig. 2.

As shown in Fig. 2, the webs 56 and 58 have been moved inwardly anddownwardly to such an extent that the tabs 70 and 73 will snap under thelower edges 88 and 92 respectively of the small panels 78 and 80. Thetabs 70 and 73 will thereafter serve to hold the small panels 78 and 80snugly against the upper triangular portions of the webs 56 and58 andthusto hold the reinforcing panel 74 flat against the main top panel 48.Continued closing of the box from the position shown in Fig. 2 willswing the webs 56 and 58 inwardly and downwardly against increasingresistance due to distortion until, as shown in Fig. 3, the webs 56 and58 have reached the position in which the triangular portions thereofbelow the lines of weakening 64 and 72 respectively will lie in a planesubstantially normal to the end walls 14 and 20. In this positionmaximum distortion occurs and the energy stored in the distorted,resilient box-board from which the container is made is at a maximum.Continued downward movement of the closure toward the position shown inFig. 4 willdepress the lower triangular portions of .the webs 56 and .58below the horizontal whereupon the energy stored in the distorted partsof the box. will be effective to spring the webs 56 2111i 58downwardlyto snap the top closure into closed position asfillustrated inFig. 4. As shown in said Fig. 4 the in folded webs 56 and 58 areinclined downwardly into the body of the box being constantly urged intosuch position by the energy stored in the distorted b x parts. When thebox is opened by lifting the top closure flap 48, 74 the webs 56 and 58will again approach the position shown in Fig. 3 and during this periodopening will be increasingly resisted. Further opening will bring abouta reversal of the direction in which the stored energy is effective andthe closure will thereupon snap into a substantially open position suchas that shown in Fig. 2.

The action of the closure of the present invention is comparable withthat achieved by the use of an overcentering spring in many familiarapplications. The spring effect in the present structure is provided bythe inherent resiliency of the box-board, which may be chipboard, kraft.board or any of the paper-boards ordinarily used in the manufacture ofcartons, folding boxes and the like. The overcentering effect is theresult of the particular construction of the webs 56 and 58 which havelines of weakening angularly offset from the natural foldlines"fo'r suchwebs. The principle of'such overcentering effect will be explained withparticular reference to the form of the invention shown in Figs. 1through 4.

Since the angle a in web 56 is slightly greater than angle b animaginary line normal to any point along the line of weakening 64 willhave a greater length between line 64 and score line 60 than it hasbetween the line 64 and score line 52. Thus, if the web 56 be foldedinwardly and the top panel 48 be folded downwardly from the flat blankshown in Fig. 1 such action would swing the end wall 14 forwardly alongthe score line 18. Because of the unequal lengths of the imaginary lineaforesaid, the end wall 14 would tend to assume a final position whereinthe angle between the rear wall 12 and the end wall 14 would be greaterthan a right angle. However, since the box is glued together and is setup in open rectangular form before the web 56 is folded inwardly, therightangular relationship between walls 12 and 14 is alreadyestablished. Thus, referring to Figs. 2 and 3, the inward folding of thewebs 56 and 58 is accompanied by the exertion of force tending to spreadthe end walls 14 and 20 apart.

Such force will be exerted along lines generally normal to the lines ofweakening 64 and 72 and thus will tend to compress or distort the lower,larger triangular portions of the webs 56 and 58. Also the force will beresisted by the end walls 14 and 20 along the fold lines 60 and 62 andwill cause bulging along such lines.

The distortion and bulging will reach a maximum when the lowertriangular portions reach a substantially horizontal or dead-centerposition. When such dead-center position is passed in a downwarddirection the distorted parts will tend to spring back to undistortedcondition and in doing so will snap the closure to closed position.

The reinforcing panel 74 and the small panels 78 and 80, if provided,serve to stiffen the top closure panel 48 and the upper, smallertriangular portions of the webs 56 and 58. Such stiffening serves toconfine distortion to the lower triangular portions of the webs 56 and58 and to the end walls 14 and 20 and makes operation of the closuremore definite and reliable particularly when relatively light board isused.

Referring now to Figs. through 8, there is shown a different form ofclosure embodying the present invention. In these figures the closure isshown applied to a box which may be generally of the size andproportions suitable for millinery. In Fig. 5 thereis shown a plan viewof the innersurface of a blank from which the box shown in Figs. 6through 8 may be erected. The blank comprises a rear wall 100, sidewalls 102 and 104 and two front wall parts, 106 and 108. The walls andwall parts aforesaid are defined by vertical score lines 110, 112, 114and 116 and the front wall parts 106, 108, are of such size that theedges 118 and 120 thereof may be overlapped to form a front wall of thesame width as the rear wall 100. A bottom closure of any desired orconvenient form may be used. For purposes of illustration, there hasbeen shown bottom end flaps 122 and 124 hinged respectively along scorelines 126 and 128 to the end walls 102 and 104. A bottom closure flap130 is hinged along a score line 132 to the rear wall 100 and isprovided with tuck-in flap 134 hinged thereto along a score line 136.

A top closure panel 138 is hinged along a score line 140 along the upperedge of the rear wall 100. In this form of the invention the top closurepanel 138 is approximately one-half the width of the open mouth of theerected box. A second top closure flap of approximately the same widthis arranged to fold along the upper edge of the front wall, the two topclosure panels thus provided being arranged to meet along a transversecenter line of the open mouth of the erected box. The second top closurepanel may be made in two parts as shown in the blank in Fig. 5 althoughit will be understood that such construction is illustrated because themain vertical seam of the box extends vertically of the front panel andit will beapparent that a different construction may be adopted in theevent-the main seam of the box liesadjacent one corner thereof or ispositioned in some other panel or wall. The second top closure panelcomprises a panel part 139 hinged along a score line 141 to the panel106 and a panel part 142 hinged along a score line 144 to the panel 108.The panel part 142 and the front Wall panel 108 are adapted to receive astripe of glue or other suitable adhesive within the area generallyindicated at 146 for the purpose of securing the edge portions and 118together to form the main seam of the box.

A'web indicated generally at 148 is hinged along a score line 150 to theend wall 102 and is also hinged along score lines 152 and 154respectively to the closure panels 138 and 139. Lines of weakeninggenerally indicated at 156 and 158 extend generally diagonally inwardlyof the web 148. The angle'e between the line of weakening 156 and thescore line 150 is slightly greater than the angle 1 between the line ofweakening 156 and the score line 152. Similarly the angle g between theline of weakening 158 and the score line 150 is greater than the angle11 between the line of weakening 158 and'the score line 154. Thedifference between these angles may be substantially the same as thatdiscussed above in connection with the first form of the presentinvention.

The upper edge of the web 148 is preferably cut away to facilitatefolding, as shown in Fig. 5. Thus the edge 160 slants downwardly fromthe upper end of score line 152 to a point of intersection with acontinuation of the line of weakening 156. A similar inclined edge 162extends from the upper end of score line 154 to a point of intersectionwith the line of weakening 158. A generally horizontal portion 164 joinsthe inclined edges 160 and 162.

A web 166, which may be identical with the web 148,

is hinged along a score line 168 to the end wall 104 and along scorelines 170 and 172 to the closure panel 138 and panel part 142respectively.

If so desired, a reinforcing panel may be provided for stiffening thetop closure made up of parts 139 and 142. Such stiffening panel maycomprise panel parts 174 and 176 hinged respectively along score lines178 and 180 to the upper edges of the top closure parts 139 and 142.Small panels 184 and 186 preferably are provided with inclined loweredges 192 and 194 which are disposed at such an angle as to coincidesubstantially with the inclined portions 160, 162 for example, of theupper edges of the webs 148 and 166 when the stiffening panel 174 isfolded flatwise into engagement with the top closure panel 139, 142.Each of the small panels 184 is provided with a notch 196 and 198 for apurpose to be described.

The line of weakening 156 in web 148 and the corresponding line ofweakening 200 in web 166 may consist primarily of a score line havingcuts 202 and 204 aligned therewith in the region of the score line 150and 168 respectively. At their outer ends the lines of weakening 156 and200 may be provided with irregular cuts to define small tabs 206 and 208respectively which will project outwardly from the webs 148 and 166 whenthe same are folded along the lines of weakening 156 and 200. Thesesmall tabs 206 and 208 are so positioned as to snap into engagement withthe notches 196 and 198 in the small stiifening panels 184 and 186, aswill be described hereinbelow.

Also, if so desired, a locking tab 210 may be formed along the upperedge of the closure panel 138. The tab 210 has tongues 212 and 214 forinsertion in openings 216 and 218 formed respectively in the closurepanel parts 139 and 142. The tab 210 (if provided) may be availed as asupplemental lock for the top closure panels.

Inasmuch as the front wall of the box is formed of corresponding halveswhich are joined along the edges 118 and 120 as described above, it ispreferable to provide a plurality of relief-notchesalong variousscore'lines in order to avoid the necessity for folding doublethicknesses of box board. Such provision is commonin the box making artand in this connection the blank may be provided with relief notches220, 222, 224 and 226 which are so shaped and located in the zone of themain seam of the box as to function in the desired manner. An inspectionof Fig. 6'wi1l reveal the ultimate disposition of the relief notches 220and 224, 226, for example.

The blank shownin Fig. 5 will be folded along two vertical score linessuch as 112 and 114 to bring the edges 118 and 120'into overlappingposition with edge 120 uppermost. Adhesive in the zone 146 will beavailed of to form the main seam of the box. The box is then ready forshipment to the customer in fiat folded form. When the box is set up itwill be creased along the remaining vertical score lines to bring it tohollow rec tangular form andthe bottom closure flaps 122, 124 and130'will be moved to closed position in known manner. The box is now setup in rectangular form with the top open topreceive contents.

When it is desired to close the boxfor the first time, the stiffeningpanel 174, 176 with associated small panels 184 and 186 is foldedinwardly and downwardly along the score lines 178, and 180 into theposition illustrated in Fig. 6. It should be noted that in Fig. 6 thebox has been turned into a position wherein the wall 100, hereinarbitrarily referred to as the rear wall, is in the front part of theview. As shown in said figure, the notch, 196 in panel 184 lies adjacenttab 206 in web 148. A'similar relation is established between the notch198 and the tab 208 attheopposite end of the box. The webs 148 and 166are thenpressed inwardly to initiate folding along the lines ofweakening 156, .158, 200 and 230. The top closure panels 138 and 139,142 will thereupon move inwardly and downwardly toward closed position.As suchmovement continues the notches 196 and 198 will become seatedbehind the tabs 206 and 208 and thereafter will remain in suchrelationship to hold the stiffening panel 174, 176 snugly against theclosure panel 139, 142.

Further movement of the closure toward closed position will bring theparts into the position shown in Fig. 7 wherein the central portions ofthe webs 148, 166 will approach a generally horizontal position.Movement up to this point meets with increasing resistance due todistortion of the webs 148' and 166 and of adjacent walls such as theend walls 102 and 104, all as explained above in connection with .Figs.1 through 4.. Maximum distortion occurs at approximately the positionillustrated in 7 Fig. .7. As the central portions of the webs 148 and166 are moved beyond the dead center position they will snap downwardlytowards the position shown in Fig. 8.

The over-centering spring action exerted by the closure shown in Figs. 5through 8 is substantially the same as that described above inconnection with Figs. 1 through 4. Thus the lines of weakening 156, 158,200 and 230 are offset from the natural fold lines of the webs 148 and166 in such manner that imaginary lines normal to the lines of weakeninghave excessive length below the lines of weakening and bring aboutdistortion as heretofore described.

It will be noted that the closure flaps 138 and 139, 142 are of suchlength as to meet in the center of the top opening of the box. It ispreferred to provide the closure panel 138 with an extension lip 232which will overlap the closure panel 139, 142 as shown in Fig. 8. In theevent a locking tab such as 210 isprovided the tongues 212 and 214thereof may be inserted in the openings 216 and 218 (see Fig. 5) to lockthe top closure flaps in the position illustrated in Fig. 8.

From the above detailed description of two embodiments of the presentinvention, it will be apparent that the principal feature of theinvention lies in the provision of'webs hingedly connected'with'-opposite ends of -a-cloarcane sure flap and with the walls adjacent thewall from which the closure flap-extends, which webs are provided withlines of weakening ofifset from the natural fold lines which such webswould tend to follow when tucked inwardly of the closure-flapas thelatter is moved towards closing position. The otfsetis such that theportion of the web lying between the line of weakening and the adjacentwall provides lever arms whose effective lengths are greater thancorresponding lever arms between the line of weakening and the edge ofthe closure flap to which-the web is joined. Thus when the flap is movedtowards closed position the web-portion having the longer lever I tomove the Webs towards a position in which distortionis reduced. Thetendency towards such movement causes the closure to spring towardsclosed position and to remain closed until sufficient force is appliedto the closure to bring the webs upwardly through the position ofmaximum distortion whereupon over-centering will again occur and thewebs will spring the closure into substantially open position.

I claim:

1. In a box made of paperboard, the combination of four rectangularlydisposed side walls, a bottom closure lying in a plane substantiallynormal to said side walls when in closed position, and a top closureincluding at least one rectangular flap hingedly joined to the 'upperedge of one of said side walls and adapted to be folded along said edgeinto a plane substantially normal to said side walls to assume a closedposition, a pair of webs, each of said webs being hingedly joined to oneside edge of said closure flap and tothe upper edge of a side wallcontiguous with that to which said closure fiap is hinged, each of saidwebs having a line of weakening formed therein extending angularly fromthe intersection of the upper edges of said contiguous wall and the wallto which said closure flap is hinged and defining an angle with theupper edge of said contiguous side wall which is slightly greater thanthe angle which it defines with the side edge of said closure flap, anda rectangular flap hinged to the free edge of said closure flap andhaving panels hinged at the opposite ends thereof, said rectangular flapbeing adapted to be folded flatwise against the inner surface of saidclosure flap to stiffen said closure flap and said panels being adaptedto lie flatwise respectively against the portions of said webs lyingabove the angularly ex tending lines of weakening therein whereby whensaid closure flap is moved to closed position said panels will serve tourge the inwardly folded webs downwardly into closure locking position.

2. In a box made of paperboard, the combination of four rectangularlydisposed side walls, a bottom closure lying in a plane substantiallynormal to said side Walls when in closed position, and a top closureincluding at least one rectangular flap hingedly joined to the upperedge of one of said side Walls and adapted to be folded along said edgeinto a plane substantially normal to said side walls to assume a closedposition, a pair of webs, each of said webs being hingedly joined to oneside edge of said closure flap and to the upper edge of a side wallcontiguous with that to which said closure flap is hinged, each of saidwebs having a line of weakening formed therein extending angularly fromthe intersection of the upper edges of said contiguous wall and the wallto which said closure flap is hinged and defining an angle with theupper edgeof said contiguous side wall which is slightly greater thanthe angle which it defines with the side edge of said closure flap, arectangular flap hinged to the free edge of said closure flap and havingpanels hinged at the opposite ends thereof, said rectangular flap beingadapted to be folded flatwise against the inner surface of said closureflap to stiffen said closure flap and said panels being adapted to liefiatwise respectively against the portions of said webs lying above theangularly extending lines of weakening therein whereby when said closureflap is moved to closed position said panels will serve to urge theinwardly folded webs downwardly into closure locking position, saidpanels terminating along a line substantially coinciding with at least apart of the length of the angularly extending lines of weakening in saidwebs, and tabs extending from the portions of said webs lying below thelines of weakening therein upwardly across said lines of weakening toengage the terminal edges of said panels when the closure is moved toclosed position thereby to lock said panels in flatwise engagement withthe portions of said webs lying above the lines of weakening therein.

3. In a box made of paperboard, the combination of four rectangularlydisposed side walls, a bottom closure lying in a plane substantiallynormal to said side walls when in closed position, and a top closureincluding at least one rectangular flap hingedly joined to the upperedge of one of said side walls and adapted to be folded along said edgeinto a plane substantially normal to said side walls to assume a closedposition, a pair of webs, each of said webs being hingedly joined to oneside edge of said closure flap and to the upper edge of a side wallcontiguous with that to which said closure flap is hinged, each of saidwebs having a line of weakening formed therein extending angularly fromthe intersection of the upper edges of said contiguous Wall and the wallto which said closure flap is hinged and defining an angle with theupper edge of said contiguous side wall which is slightly greater thanthe angle which it defines with the side edge of said closure flap, arectangular flap hinged to the free edge of said closure flap and havingpanels hinged at the opposite ends thereof, said rectangular flap beingadapted to be folded fiatwise against the inner surface of said closureflap to stiffen said cloure flap and said panels being adapted to lieflatwise respectively against the portions of said webs lying above theangularly extending lines of weakening therein whereby when said closureflap is moved to closed position said panels will serve to urge theinwardly folded webs downwardly into closure locking position, saidpanels terminating along a line substantially coinciding with at least apart of the length of the angularly extending lines of weakening in saidwebs, notches formed in the terminal edges of each of said panels, andtabs extending from the portions of said webs lying'below the lines ofweakening therein upwardly across said lines of weakening to engage thenotches in the terminal edges of said panels when the closure is movedto closed position thereby to lock said panels in flatwise engagementwith the portions of said webs lying above the lines of weakeningtherein.

References Cited in the file of this patent UNITED STATES PATENTS1,103,186 Feldmeyer July 14, 1914 2,002,005 Gottlieb May 21, 19352,317,223 Rottman Apr. 20, 1943 2,326,417 Ullrich Aug. 10, 19432,336,731 Henderson Dec. 14, 1943 FOREIGN PATENTS 22,313 Great BritainOct. 10, 1911 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatent No. 2,799,442 July 16, 1957 Robert E. Van Rosen It is herebycertified that error appears in the above numbered patent requiringcorrection and that the said Letters Patent should read as correctedbelow.

In the grant, lines 2 and 3, for 'assig'nor to Robert Gair Company, Inc.of New York, N. Y. a corporation of Delaware" read --assignor toContinental Can Company, Inc. a corporation of New York-; line 12, for"Robert Gair Company, Inc. its successors" read --Continental CanCompany, Inc. its successors--; in the heading to the printedspecification, lines 3 to 5, inclusive, for "assignor to Robert GairCompany, Inc. New York, N. Y. a corporation of Delaware" read --assignorto Continental Can Company, Inc. a corporation of New York--.

Signed and sealed this 3rd day of December 1957.

iSEAL) ttest: KARL H. AXLINE ROBERT C. WATSON Attestlng OfficerComnissioner of Patents

